Sanders supporters don't really care so much about party brand loyaly. They are fired up about his policy positions. After the last 30 years, who wouldn't be? That's why practically every other Democratic candidate has adopted at least some of his policy as their own positions. Funny how that worked. Not bad for an old geezer.... His age isn't ideal but he seems spry enough for 1 million volunteers. Maybe once they hear he's not a member of club DEM they'll mutiny? If all you got on the guy is 'he's not a true democrat' I think that's going to fall on a lot of deaf ears. May even help with independents.